1. Put all but the last
three ingredients in a large saucepan, stir well and bring to a boil. 2. After 3-4 minutes on the boil, lower heat to
a fast simmer. 3. Cook for 20-25 minutes, stirring occasionally. Spoon off and discard any scum on the surface. 4.
Add the vermicelli and cook for a further 10 minutes. Stir frequently. 5. If you like, you can buzz this up in the food
processor, but it's really not necessary. 6. Ladle into bowls and top with sour cream, cilantro (if desired) and more
black pepper (if desired).